I dont understand the Slow Fast thing

I hear about headphones being “Slow” or “Fast”. I really dont understand this. I plug the headphones in and i hear the music when the signal is fed to it lol. Fast, slow, i dont get it

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It’s not really something to worry about too much. A fast headphone will have faster transient response and decay and may be more detailed because of this. This may make headphones sound “tight” or “cleaner” with bass that might sound noticeably quicker because of the fast roll off. A slower headphone may not be a detailed but may sound more natural sounding with boomier (if that’s a word) bass. It all depends on the headphone. Typically fast headphones will also come off as brighter and slower ones as warmer. Quick sounds may also be more aurally stimulating to the ear (like a tickle almost). Its pretty much regarding timing of sound a little bit. An easy comparison is a “fast” planar vs a “slower dynamic”. Let’s take the fostex tr-x00 vs the hifiman sundara. The sundara has quicker transients and the bass comes across as more sterile and quick sounding, where the fostex is loud, boomy, and has lots of impact. Bass is an easy way to show this imo.

But realistically its not something to worry about. All headphones sound different regardless to how “fast” they are, so I would be more concerned about the other aspects

Edit: a simple way of explaining transients and decay is that when they are shorter, sounds stop making noise quicker. If that simplistic definition helps. Also faster headphones usally come across as having better separation because they can play more sounds quicker (why use many word when one word do trick)

It’s also why people like electrostatics because they can reproduce sound very quickly compared to other drivers and maintain high levels of detail and separation


As MON said…fast responses are a bit like 2 stoke engines, quick revving, fast and over quickly… where as slower response phones are more akin to 4 strokes, smoother with an audio/power curve that’s as not as immediate but can be as powerful non the less and decay slower.

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Well that’s a good way of putting it. Have never thought of it like that, that’s a pretty easy example to understand. I guess I can also say then that 4 strokes are catching up to the responsiveness to 2 strokes, and that teslas or other electrics are estats lol

So dynamic’s are 4 strokes, planar are 2 strokes, and estats are electrics?

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Okay so it sounds like fast is preferable to slow. and is even connected to detail. thanks for the info guys!

Membrane speed is to me what really separates hi-fi headphones from average/mediocre/consumer-grade headphones, and the main thing I noticed when my eyes went popping out the first time I listened to the Superlux HD668B. High membrane speed is necessary for accurate reproduction of all of the steepest slopes in the original signal’s waveform as well as all the direction changes (“turns on a dime” or takes a while and ends up “rounding out” the waveform on sudden changes of direction). So it’s an absolute requirement for resolution and ultimate fidelity. You care about high fidelity of music reproduction, you have to care about membrane speed.

But then again, like M0N said, you can’t just go for crazy membrane speed (electrostatics) and ignore everything else, because with the highest speed technologies we have today you will lose other important aspects of fidelity like frequency response and dynamics/impact. The sweet spot today seems to be somewhere in the area of ToTL dynamic (Beyerdynamic DT 880/600-ohm, Sennheiser HD800S, Focal Utopia/Clear/etc., ZMF Auteur/etc.) and ToTL planar magnetic headphones (not sure, HiFiMan Arya, Abyss 1266 or some other Abyss? Audeze-something?). For me the best marriage of speed, FR and dynamics so far at a reasonable price is the Verum 1, and I will probably stop searching once I’m done evaluating and EQ-ing these.


Pretty much. The sweet spot is very subjective tbh and not something to really worry about. Personally for me it’s planar if the goal of the sweet spot is a balance of resolution and naturalness, but that doesn’t mean that I don’t enjoy high end dynamics.

Just look at headphones individually and find out which one you want that way, I wouldn’t recommend to go look for the fastest out there or whatnot. Just take each headphone for what it is and just kinda disregard the driver type unless it effects the sound in a way that matters to you